《零基础入门学习Python》第092讲：Pygame：飞机大战3

逃离我推掉我的手 2022-04-10 12:10 233阅读 0赞

当敌我两机发生碰撞时，两方应该是玉石俱焚的，现在我为每一个类增加撞击时发生的惨烈画面，比如：

enemy1：

![20190107094422807.png][]

enemy2：

![20190107094539979.png][]

enemy3：

![2019010709462197.png][]

me：

![20190107094719928.png][]

我们现在就来写代码：

首先为每一个类把这些图片加进去：

#myplane.py 部分代码
    import pygame
    
    class Myplane(pygame.sprite.Sprite):
            def __init__(self, bg_size):
                    pygame.sprite.Sprite.__init__(self)
    
                    self.image1 = pygame.image.load("images/me1.png").convert_alpha()
                    self.image2 = pygame.image.load("images/me2.png").convert_alpha()
                    #添加坠机图片
                    self.destroy_images = []
                    self.destroy_images.extend([\
                        pygame.image.load("images/me_destroy_1.png").convert_alpha(), \
                        pygame.image.load("images/me_destroy_2.png").convert_alpha(), \
                        pygame.image.load("images/me_destroy_3.png").convert_alpha(), \
                        pygame.image.load("images/me_destroy_4.png").convert_alpha() \
                        ])
                    self.rect = self.image1.get_rect()
                    self.width, self.height = bg_size[0], bg_size[1]
                    self.rect.left, self.rect.top = \
                                    (self.width - self.rect.width) // 2, \
                                    self.height - self.rect.height - 60  #减60，留给状态栏
                    self.speed = 10

#enemy.py
    import pygame
    from random import *
    
    class SmallEnemy(pygame.sprite.Sprite):
            def __init__(self, bg_size):
                    pygame.sprite.Sprite.__init__(self)
    
                    self.image = pygame.image.load("images/enemy1.png").convert_alpha()
                    #添加坠机图片
                    self.destroy_images = []
                    self.destroy_images.extend([\
                            pygame.image.load("images/enemy1_down1.png").convert_alpha(), \
                            pygame.image.load("images/enemy1_down2.png").convert_alpha(), \
                            pygame.image.load("images/enemy1_down3.png").convert_alpha(), \
                            pygame.image.load("images/enemy1_down4.png").convert_alpha() \
                            ])
                    self.rect = self.image.get_rect()
                    self.width, self.height = bg_size[0], bg_size[1]
                    self.speed = 2        
                    self.rect.left, self.rect.top = \
                                    randint(0, self.width - self.rect.width), \
                                    randint(-5 * self.height, 0)  #在页面外部上方5个屏幕高度范围内随机生成一个敌机      
    
            def move(self):
                    if self.rect.top < self.height:
                            self.rect.top += self.speed
                    else:
                            self.reset()
    
            def reset(self):        
                    self.rect.left, self.rect.top = \
                                    randint(0, self.width - self.rect.width), \
                                    randint(-5 * self.height, 0)
    
    class MidEnemy(pygame.sprite.Sprite):    
            def __init__(self, bg_size):
                    pygame.sprite.Sprite.__init__(self)
    
                    self.image = pygame.image.load("images/enemy2.png").convert_alpha()
                    #添加坠机图片
                    self.destroy_images = []
                    self.destroy_images.extend([\
                            pygame.image.load("images/enemy2_down1.png").convert_alpha(), \
                            pygame.image.load("images/enemy2_down2.png").convert_alpha(), \
                            pygame.image.load("images/enemy2_down3.png").convert_alpha(), \
                            pygame.image.load("images/enemy2_down4.png").convert_alpha() \
                            ])
                    self.rect = self.image.get_rect()
                    self.width, self.height = bg_size[0], bg_size[1]
                    self.speed = 1
                    self.rect.left, self.rect.top = \
                                    randint(0, self.width - self.rect.width), \
                                    randint(-10 * self.height, -self.height) #在页面外部上方1个到10个屏幕高度范围内随机生成一个敌机（1-10个，就保证了不会一开始出大一个大的）
    
            def move(self):
                    if self.rect.top < self.height:
                            self.rect.top += self.speed
                    else:
                            self.reset()
    
            def reset(self):
                    self.rect.left, self.rect.top = \
                                    randint(0, self.width - self.rect.width), \
                                    randint(-10 * self.height, -self.height)
    
    class BigEnemy(pygame.sprite.Sprite):    
            def __init__(self, bg_size):
                    pygame.sprite.Sprite.__init__(self)
    
                    #大型敌机有飞行特效，两张图片切换
                    self.image1 = pygame.image.load("images/enemy3_n1.png").convert_alpha()
                    self.image2 = pygame.image.load("images/enemy3_n2.png").convert_alpha()
                    #添加坠机图片
                    self.destroy_images = []
                    self.destroy_images.extend([\
                            pygame.image.load("images/enemy3_down1.png").convert_alpha(), \
                            pygame.image.load("images/enemy3_down2.png").convert_alpha(), \
                            pygame.image.load("images/enemy3_down3.png").convert_alpha(), \
                            pygame.image.load("images/enemy3_down4.png").convert_alpha(), \
                            pygame.image.load("images/enemy3_down5.png").convert_alpha(), \
                            pygame.image.load("images/enemy3_down6.png").convert_alpha() \
                            ])
                    self.rect = self.image1.get_rect()
                    self.width, self.height = bg_size[0], bg_size[1]
                    self.speed = 1
                    self.rect.left, self.rect.top = \
                                    randint(0, self.width - self.rect.width), \
                                    randint(-15 * self.height, -5 * self.height) #在页面外部上方5-15个屏幕高度范围内随机生成一个敌机
    
            def move(self):
                    if self.rect.top < self.height:
                            self.rect.top += self.speed
                    else:
                            self.reset()
    
            def reset(self):
                    self.rect.left, self.rect.top = \
                                    randint(0, self.width - self.rect.width), \
                                    randint(-15 * self.height, -5 * self.height)

接下来我们要为每一个类添加 active 属性，该属性表示 还活着，也就是说，当该属性的值为 True 时，我们就让飞机显示正常的飞行状态，而当该属性为 False 时，表示该飞机已经遇难了，我们就要依次显示 坠机的画面，显示完之后，调用该类的 resert() 方法。

self.active = True

接下来修改 main 模块的main() 函数，在绘制每一种飞机时，先检测它的 active 的值：

#main.py 部分代码
            #中弹图片索引
            e1_destroy_index = 0
            e2_destroy_index = 0
            e3_destroy_index = 0
            me_destroy_index = 0
    (此处代码省略)
                    #绘制大型敌机
                    for each in big_enemies:
                            if each.active: #检测是否还活着
                                    each.move()
                                    if switch_image:
                                            screen.blit(each.image1, each.rect)
                                    else:
                                            screen.blit(each.image2, each.rect)
                                    #即将出现在界面中，播放音效
                                    if each.rect.bottom > -50:
                                            enemy3_fly_sound.play()
                            else:
                                    #坠机
                                    enemy3_down_sound.play() #音效
                                    if not(delay % 3):
                                            screen.blit(each.destroy_images[e3_destroy_index], each.rect)
                                            e3_destroy_index = (e3_destroy_index + 1) % 6
                                            if e3_destroy_index == 0:
                                                    each.reset()
    
    （其他敌机和我方飞机代码类似。。。。。）

我们接着就要写碰撞检测代码：

一旦我方飞机碰撞到敌机，导致的结果必将是敌我同归于尽。

#main.py 部分代码
                    #检测我方飞机是否被撞
                    enemies_down = pygame.sprite.spritecollide(me, enemies, False)
                    if enemies_down:
                            me.active = False
                            for e in enemies_down:
                                    e.active = False

我们碰撞检测使用  spritecollide() 方法：

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQxNTU2MzE4_size_16_color_FFFFFF_t_70][]

碰撞和坠机是实现了，但是我们发现，两个飞机还没真正的接触就已经撞上了，这是为什么呢？

这是因为我们使用了普通的 spritecollide() 方法，这个方法默认情况下是以图片的矩形位置区域作为检测的范围，而我们飞机的矩形范围远大于自身，但是我们完全是可以做得更好的，我们可以做到完美的碰撞检测，怎么实现呢？

**sprite 模块里有一个叫做 collide\_mask 的函数可以利用，这个函数要求检测对象拥有一个 mask 属性，这个属性就是用于指定检测的范围，关于 mask，Pygame 还专门写了一个 mask 模块，其中有一个叫做 from\_surface() 的函数，可以将 Surface 对象中非透明的部分标记为 mask 并返回。**

首先，给每个类加上 mask 属性：

self.mask = pygame.mask.from_sueface(self.image) #将非透明部分标记为mask

然后在main 函数中修改碰撞检测代码，指定检测方法为 pygame.sprite.collide\_mask，即：

#main.py
                    #检测我方飞机是否被撞
                    enemies_down = pygame.sprite.spritecollide(me, enemies, False, pygame.sprite.collide_mask)
                    if enemies_down:
                            me.active = False
                            for e in enemies_down:
                                    e.active = False

好了，这就是完美的碰撞检测了，在大部分情况下编写游戏开发，基本上都是使用这种碰撞检测。

现在，有人就可能已经发现了，刚才我们的代码实际上是存在很明显的Bug，导致部分音效无法正常播放，

大家知道是为什么吗？可以看一下这里的代码：

#绘制大型敌机
                    for each in big_enemies:
                            if each.active: #检测是否还活着
                                    each.move()
                                    if switch_image:
                                            screen.blit(each.image1, each.rect)
                                    else:
                                            screen.blit(each.image2, each.rect)
                                    #即将出现在界面中，播放音效
                                    if each.rect.bottom > -50:
                                            enemy3_fly_sound.play()
                            else:
                                    #坠机
                                    enemy3_down_sound.play() #音效
                                    if not(delay % 3):
                                            screen.blit(each.destroy_images[e3_destroy_index], each.rect)
                                            e3_destroy_index = (e3_destroy_index + 1) % 6
                                            if e3_destroy_index == 0:
                                                    each.reset()

大家看看，不管是我们的飞机，还是敌机，它们是怎么坠机的，首先，我们检测 active，如果为False 的话，就播放音效，然后画一张坠机图，这样就一帧过去了，然后第二帧，又播放音效，画图的进不去，然后第三帧，播放音效，然后画下面的一张坠机图。

大家发现问题没有，你要画它坠机的图片，需要好多帧，但是这里你重复的播放了好多次它坠机的音效，一个飞机坠机只需要播放一次音效即可，你要播放很多次，导致的结果就是你把所有音效的通道都占满了，因为Pygame 默认只有8条音效的通道。

我们现在要做的就是让它只播放一次。修改如下：

#绘制大型敌机
                    for each in big_enemies:
                            if each.active: #检测是否还活着
                                    each.move()
                                    if switch_image:
                                            screen.blit(each.image1, each.rect)
                                    else:
                                            screen.blit(each.image2, each.rect)
                                    #即将出现在界面中，播放音效
                                    if each.rect.bottom > -50:
                                            enemy3_fly_sound.play()
                            else:
                                    #坠机                                
                                    if not(delay % 3):
                                            if e3_destroy_index == 0:
                                                    enemy3_down_sound.play() #音效
                                            screen.blit(each.destroy_images[e3_destroy_index], each.rect)
                                            e3_destroy_index = (e3_destroy_index + 1) % 6
                                            if e3_destroy_index == 0:
                                                    each.reset()

现在再来测试一下就好多了，当然，如果你嫌默认的8个音效通道太少的话，可以使用 mixer 模块的 set\_*num*\_channels() 方法来设置通道数多一点。

下面贴出这节课实现的3个模块的完整代码：

#main.py
    import pygame
    import sys
    import traceback #为了更好地退出
    import myplane
    import enemy
    
    from pygame.locals import *
    
    pygame.init()
    pygame.mixer.init()  #混音器初始化
    
    bg_size = width, height = 480, 700
    screen = pygame.display.set_mode(bg_size)
    pygame.display.set_caption("飞机大战 -- Python Demo")
    
    background = pygame.image.load("images/background.png").convert()
    
    # 载入游戏音乐
    pygame.mixer.music.load("sound/game_music.ogg")
    pygame.mixer.music.set_volume(0.2)
    bullet_sound = pygame.mixer.Sound("sound/bullet.wav")
    bullet_sound.set_volume(0.2)
    bomb_sound = pygame.mixer.Sound("sound/use_bomb.wav")
    bomb_sound.set_volume(0.2)
    supply_sound = pygame.mixer.Sound("sound/supply.wav")
    supply_sound.set_volume(0.2)
    get_bomb_sound = pygame.mixer.Sound("sound/get_bomb.wav")
    get_bomb_sound.set_volume(0.2)
    get_bullet_sound = pygame.mixer.Sound("sound/get_bullet.wav")
    get_bullet_sound.set_volume(0.2)
    upgrade_sound = pygame.mixer.Sound("sound/upgrade.wav")
    upgrade_sound.set_volume(0.2)
    enemy3_fly_sound = pygame.mixer.Sound("sound/enemy3_flying.wav")
    enemy3_fly_sound.set_volume(0.5)
    enemy1_down_sound = pygame.mixer.Sound("sound/enemy1_down.wav")
    enemy1_down_sound.set_volume(0.2)
    enemy2_down_sound = pygame.mixer.Sound("sound/enemy2_down.wav")
    enemy2_down_sound.set_volume(0.2)
    enemy3_down_sound = pygame.mixer.Sound("sound/enemy3_down.wav")
    enemy3_down_sound.set_volume(0.5)
    me_down_sound = pygame.mixer.Sound("sound/me_down.wav")
    me_down_sound.set_volume(0.2)
    
    def add_small_enemies(group1, group2, num):
            for i in range(num):
                    e1 = enemy.SmallEnemy(bg_size)
                    group1.add(e1)
                    group2.add(e1)
    
    def add_mid_enemies(group1, group2, num):
            for i in range(num):
                    e2 = enemy.MidEnemy(bg_size)
                    group1.add(e2)
                    group2.add(e2)
    
    def add_big_enemies(group1, group2, num):
            for i in range(num):
                    e3 = enemy.BigEnemy(bg_size)
                    group1.add(e3)
                    group2.add(e3)
    
    def main():
            pygame.mixer.music.play(-1)
    
            # 生成我方飞机
            me = myplane.Myplane(bg_size)
    
            #生成敌方飞机
            enemies = pygame.sprite.Group()
    
            # 生成敌方小型飞机
            small_enemies = pygame.sprite.Group()
            add_small_enemies(small_enemies, enemies, 15)
    
            # 生成敌方中型飞机
            mid_enemies = pygame.sprite.Group()
            add_mid_enemies(mid_enemies, enemies, 4)
    
            # 生成敌方大型飞机
            big_enemies = pygame.sprite.Group()
            add_big_enemies(big_enemies, enemies, 2)
    
            #中弹图片索引
            e1_destroy_index = 0
            e2_destroy_index = 0
            e3_destroy_index = 0
            me_destroy_index = 0
            
            clock = pygame.time.Clock()
    
            #用于切换图片
            switch_image = True
    
            #用于延迟
            delay = 100
    
            running = True
    
            while running:
                    for event in pygame.event.get():
                            if event.type == QUIT:
                                    pygame.quit()
                                    sys.exit()
                                    
                    #检测用户的键盘操作
                    key_pressed = pygame.key.get_pressed()
    
                    if key_pressed[K_w] or key_pressed[K_UP]:
                            me.moveUp()
                    if key_pressed[K_s] or key_pressed[K_DOWN]:
                            me.moveDown()
                    if key_pressed[K_a] or key_pressed[K_LEFT]:
                            me.moveLeft()
                    if key_pressed[K_d] or key_pressed[K_RIGHT]:
                            me.moveRight()                        
    
                    screen.blit(background, (0, 0))
    
                    #绘制大型敌机
                    for each in big_enemies:
                            if each.active: #检测是否还活着
                                    each.move()
                                    if switch_image:
                                            screen.blit(each.image1, each.rect)
                                    else:
                                            screen.blit(each.image2, each.rect)
                                    #即将出现在界面中，播放音效
                                    if each.rect.bottom == -50:
                                            enemy3_fly_sound.play(-1) #循环播放
                            else:
                                    #坠机
                                    if not(delay % 3):
                                            if e3_destroy_index == 0:
                                                    enemy3_down_sound.play()
                                            screen.blit(each.destroy_images[e3_destroy_index], each.rect)
                                            e3_destroy_index = (e3_destroy_index + 1) % 6
                                            if e3_destroy_index == 0:
                                                    enemy3_fly_sound.stop() #循环音效停止播放
                                                    each.reset()
                                    
                    #绘制中型敌机
                    for each in mid_enemies:
                            if each.active: #检测是否还活着
                                    each.move()                     
                                    screen.blit(each.image, each.rect)
                            else:
                                    #坠机
                                    if not(delay % 3):
                                            if e2_destroy_index == 0:
                                                    enemy2_down_sound.play() #音效
                                            screen.blit(each.destroy_images[e2_destroy_index], each.rect)
                                            e2_destroy_index = (e2_destroy_index + 1) % 4
                                            if e2_destroy_index == 0:
                                                    each.reset()
    
                    #绘制小型敌机
                    for each in small_enemies:
                            if each.active: #检测是否还活着
                                    each.move()                     
                                    screen.blit(each.image, each.rect)
                            else:
                                    #坠机
                                    if not(delay % 3):
                                            if e1_destroy_index == 0:
                                                    enemy1_down_sound.play() #音效                                
                                            screen.blit(each.destroy_images[e1_destroy_index], each.rect)
                                            e1_destroy_index = (e1_destroy_index + 1) % 4
                                            if e1_destroy_index == 0:
                                                    each.reset()
            
                    #检测我方飞机是否被撞
                    enemies_down = pygame.sprite.spritecollide(me, enemies, False, pygame.sprite.collide_mask)
                    if enemies_down:
                            #me.active = False
                            for e in enemies_down:
                                    e.active = False
                                    
                    
                    #绘制我方飞机
                    if me.active: #检测是否还活着
                            if switch_image:
                                    screen.blit(me.image1, me.rect)
                            else:
                                    screen.blit(me.image2, me.rect)
                    else:
                            #坠机
                            if not(delay % 3):
                                    if me_destroy_index == 0:
                                            me_down_sound.play()                        
                                    screen.blit(me.destroy_images[me_destroy_index], me.rect)
                                    me_destroy_index = (me_destroy_index + 1) % 4
                                    if me_destroy_index == 0:
                                            print("game over")
                                            running = False
    
                    #切换图片
                    if not(delay % 5):  #5帧切换一次，一秒就只切换12次
                            switch_image = not switch_image                        
    
                    delay -= 1
                    if not delay:
                            delay = 100
    
                    pygame.display.flip()
    
                    clock.tick(60)
    
    if __name__ == "__main__":
            try:
                    main()
            except SystemExit:
                    pass
            except:
                    traceback.print_exc()
                    pygame.quit()
                    input()

#myplane.py
    import pygame
    
    class Myplane(pygame.sprite.Sprite):
            def __init__(self, bg_size):
                    pygame.sprite.Sprite.__init__(self)
    
                    self.image1 = pygame.image.load("images/me1.png").convert_alpha()
                    self.image2 = pygame.image.load("images/me2.png").convert_alpha()
                    #添加坠机图片
                    self.destroy_images = []
                    self.destroy_images.extend([\
                        pygame.image.load("images/me_destroy_1.png").convert_alpha(), \
                        pygame.image.load("images/me_destroy_2.png").convert_alpha(), \
                        pygame.image.load("images/me_destroy_3.png").convert_alpha(), \
                        pygame.image.load("images/me_destroy_4.png").convert_alpha() \
                        ])
                    self.rect = self.image1.get_rect()
                    self.width, self.height = bg_size[0], bg_size[1]
                    self.rect.left, self.rect.top = \
                                    (self.width - self.rect.width) // 2, \
                                    self.height - self.rect.height - 60  #减60，留给状态栏
                    self.speed = 10
                    self.active = True
                    self.mask = pygame.mask.from_surface(self.image1) #将非透明部分标记为mask
    
            def moveUp(self):
                    if self.rect.top > 0:
                            self.rect.top -= self.speed
                    else:
                            self.rect.top = 0
    
            def moveDown(self):
                    if self.rect.bottom < self.height - 60:
                            self.rect.top += self.speed
                    else:
                            self.rect.bottom = self.height - 60
    
            def moveLeft(self):
                    if self.rect.left > 0:
                            self.rect.left -= self.speed
                    else:
                            self.rect.left = 0
    
            def moveRight(self):
                    if self.rect.right < self.width:
                            self.rect.left += self.speed
                    else:
                            self.rect.right = self.width

#enemy.py
    import pygame
    from random import *
    
    class SmallEnemy(pygame.sprite.Sprite):
            def __init__(self, bg_size):
                    pygame.sprite.Sprite.__init__(self)
    
                    self.image = pygame.image.load("images/enemy1.png").convert_alpha()
                    #添加坠机图片
                    self.destroy_images = []
                    self.destroy_images.extend([\
                            pygame.image.load("images/enemy1_down1.png").convert_alpha(), \
                            pygame.image.load("images/enemy1_down2.png").convert_alpha(), \
                            pygame.image.load("images/enemy1_down3.png").convert_alpha(), \
                            pygame.image.load("images/enemy1_down4.png").convert_alpha() \
                            ])
                    self.rect = self.image.get_rect()
                    self.width, self.height = bg_size[0], bg_size[1]
                    self.speed = 2
                    self.active = True
                    self.rect.left, self.rect.top = \
                                    randint(0, self.width - self.rect.width), \
                                    randint(-5 * self.height, 0)  #在页面外部上方5个屏幕高度范围内随机生成一个敌机
                    self.mask = pygame.mask.from_surface(self.image) #将非透明部分标记为mask
    
            def move(self):
                    if self.rect.top < self.height:
                            self.rect.top += self.speed
                    else:
                            self.reset()
    
            def reset(self):
                    self.active = True
                    self.rect.left, self.rect.top = \
                                    randint(0, self.width - self.rect.width), \
                                    randint(-5 * self.height, 0)
    
    class MidEnemy(pygame.sprite.Sprite):    
            def __init__(self, bg_size):
                    pygame.sprite.Sprite.__init__(self)
    
                    self.image = pygame.image.load("images/enemy2.png").convert_alpha()
                    #添加坠机图片
                    self.destroy_images = []
                    self.destroy_images.extend([\
                            pygame.image.load("images/enemy2_down1.png").convert_alpha(), \
                            pygame.image.load("images/enemy2_down2.png").convert_alpha(), \
                            pygame.image.load("images/enemy2_down3.png").convert_alpha(), \
                            pygame.image.load("images/enemy2_down4.png").convert_alpha() \
                            ])
                    self.rect = self.image.get_rect()
                    self.width, self.height = bg_size[0], bg_size[1]
                    self.speed = 1
                    self.active = True
                    self.rect.left, self.rect.top = \
                                    randint(0, self.width - self.rect.width), \
                                    randint(-10 * self.height, -self.height) #在页面外部上方1个到10个屏幕高度范围内随机生成一个敌机（1-10个，就保证了不会一开始出大一个大的）
                    self.mask = pygame.mask.from_surface(self.image) #将非透明部分标记为mask
    
            def move(self):
                    if self.rect.top < self.height:
                            self.rect.top += self.speed
                    else:
                            self.reset()
    
            def reset(self):
                    self.active = True
                    self.rect.left, self.rect.top = \
                                    randint(0, self.width - self.rect.width), \
                                    randint(-10 * self.height, -self.height)
    
    class BigEnemy(pygame.sprite.Sprite):    
            def __init__(self, bg_size):
                    pygame.sprite.Sprite.__init__(self)
    
                    #大型敌机有飞行特效，两张图片切换
                    self.image1 = pygame.image.load("images/enemy3_n1.png").convert_alpha()
                    self.image2 = pygame.image.load("images/enemy3_n2.png").convert_alpha()
                    #添加坠机图片
                    self.destroy_images = []
                    self.destroy_images.extend([\
                            pygame.image.load("images/enemy3_down1.png").convert_alpha(), \
                            pygame.image.load("images/enemy3_down2.png").convert_alpha(), \
                            pygame.image.load("images/enemy3_down3.png").convert_alpha(), \
                            pygame.image.load("images/enemy3_down4.png").convert_alpha(), \
                            pygame.image.load("images/enemy3_down5.png").convert_alpha(), \
                            pygame.image.load("images/enemy3_down6.png").convert_alpha() \
                            ])
                    self.rect = self.image1.get_rect()
                    self.width, self.height = bg_size[0], bg_size[1]
                    self.speed = 1
                    self.active = True
                    self.rect.left, self.rect.top = \
                                    randint(0, self.width - self.rect.width), \
                                    randint(-15 * self.height, -5 * self.height) #在页面外部上方5-15个屏幕高度范围内随机生成一个敌机
                    self.mask = pygame.mask.from_surface(self.image1) #将非透明部分标记为mask
    
            def move(self):
                    if self.rect.top < self.height:
                            self.rect.top += self.speed
                    else:
                            self.reset()
    
            def reset(self):
                    self.active = True
                    self.rect.left, self.rect.top = \
                                    randint(0, self.width - self.rect.width), \
                                    randint(-15 * self.height, -5 * self.height)

（未完待续）

[20190107094422807.png]: /images/20220330/a74f59d8291244ae8304ebe85cb7c3cd.png
[20190107094539979.png]: /images/20220330/9451432e64074f0aa50c9c18de14d076.png
[2019010709462197.png]: /images/20220330/e9abb271913a45be8e275746e6e69156.png
[20190107094719928.png]: /images/20220330/0c655d04c57e47a3b924befdf3cb657f.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQxNTU2MzE4_size_16_color_FFFFFF_t_70]: /images/20220330/40d5ebe7d0ee4686a6673819fa3d5d60.png